This invention relates to the isomerization of tetrahydrotricyclopentadienes, hereinafter referred to as THTCPD. More particularly the invention relates to the preparation of an isomeric mixture from THTCPD. Still more particularly the invention relates to the catalytic isomerization of THTCPD.
The resulting isomeric liquid mixture can be used as a low pour point, high energy missile fuel. Such fuels can be used in either jet or rocket propulsion. Jet propulsion includes a jet engine which can be used for a missile, an aircraft and others and includes the three basic types, i.e., ramjet, turbo-jet and pulse jet. The term rocket generally refers to a device containing its own oxygen or oxidizing agent. An article in Aviation Week and Space Technology, Jan. 26, 1976, pages 111-113, discloses some of the high density hydrocarbon fuels that are under consideration as missile fuels.
U.S. Pat. No. 3,381,046 discloses the treatment of endo-tetrahydrodicyclopentadiene with an acidic reagent to effect isomerization to the corresponding exo-isomer. This patent also discloses generally that a Lewis acid, such as aluminum chloride, can be used to isomerize endo-tetrahydrodicyclopentadiene to its exo-form. However, it cautions that the isomerization can proceed beyond the exo-diene to form undesirable compounds.